# could not resolve the tns **URL:** \ **Category:** Toad for Oracle & DevOps Toolkit\ **Created:** [June 25, 2013, 11:35am UTC](https://forums.toadworld.com/t/could-not-resolve-the-tns/19291 "2013-06-25T11:35:32Z")\ **Posts on this page:** 2\ **Page:** 1
**Author:** ![tps4eee](https://avatars.discourse-cdn.com/v4/letter/t/c6cbf5/32.png) [@tps4eee](https://forums.toadworld.com/u/tps4eee)\ **Post date:** [June 25, 2013, 11:35am UTC](https://forums.toadworld.com/t/could-not-resolve-the-tns/19291/1 "2013-06-25T11:35:32Z")
Hi All, I am new to toad. I have installed the oracle 10g xe express edition .After that installed toad 9.5 version . When i tried to open the toad and connect to local database which i installed on my laptop ,toad always says could not identify the connect string XE. please help . below are the configuration parameters. My tnsnames.ora is in the directory C:\oraclexe\app\oracle\product\10.2.0\server\NETWORK\ADMIN. My contents of tnsnames is as follows. XE = (DESCRIPTION = (ADDRESS = (PROTOCOL = TCP)(HOST = PrabhuKumarTapp)(PORT = 1521)) (CONNECT\_DATA = (SERVER = DEDICATED) (SERVICE\_NAME = XE) ) ) EXTPROC\_CONNECTION\_DATA = (DESCRIPTION = (ADDRESS\_LIST = (ADDRESS = (PROTOCOL = IPC)(KEY = EXTPROC\_FOR\_XE)) ) (CONNECT\_DATA = (SID = PLSExtProc) (PRESENTATION = RO) ) ) ## ORACLR\_CONNECTION\_DATA = (DESCRIPTION = (ADDRESS\_LIST = (ADDRESS = (PROTOCOL = IPC)(KEY = EXTPROC\_FOR\_XE)) ) (CONNECT\_DATA = (SID = CLRExtProc) (PRESENTATION = RO) ) ) My sqlnet.ora file contents are like the below . # This file is actually generated by netca. But if customers choose to # install “Software Only”, this file wont exist and without the native # authentication, they will not be able to connect to the database on NT. # The following parameters were set by TOAD ## NAMES.DIRECTORY\_PATH=(TNSNAMES) SQLNET.AUTHENTICATION\_SERVICES=(NTS) LOG\_DIRECTORY\_CLIENT=C:\oraclexe\app\oracle\product\10.2.0\server\Network\Log LOG\_FILE\_CLIENT=sqlnet\_log SQLNET.EXPIRE\_TIME=0 TRACE\_DIRECTORY\_CLIENT=C:\oraclexe\app\oracle\product\10.2.0\server\Network\Trace TRACE\_FILE\_CLIENT=sqlnet\_trc TRACE\_FILELEN\_CLIENT=100 TRACE\_FILENO\_CLIENT=3 TRACE\_LEVEL\_CLIENT=OFF TRACE\_TIMESTAMP\_CLIENT=ON TRACE\_UNIQUE\_CLIENT=ON USE\_DEDICATED\_SERVER=OFF my listener.ora is as follows. SID\_LIST\_LISTENER = (SID\_LIST = (SID\_DESC = (SID\_NAME = PLSExtProc) (ORACLE\_HOME = C:\oraclexe\app\oracle\product\10.2.0\server) (PROGRAM = extproc) ) (SID\_DESC = (SID\_NAME = CLRExtProc) (ORACLE\_HOME = C:\oraclexe\app\oracle\product\10.2.0\server) (PROGRAM = extproc) ) ) LISTENER = (DESCRIPTION\_LIST = (DESCRIPTION = (ADDRESS = (PROTOCOL = IPC)(KEY = EXTPROC\_FOR\_XE)) (ADDRESS = (PROTOCOL = TCP)(HOST = PrabhuKumarTapp)(PORT = 1521)) ) ) DEFAULT\_SERVICE\_LISTENER = (XE) * * * when i try to open new connection in toad . i could see SQLNET Editor button and TNSNAMES Editor are enabled. When i click on SQLNET Editor i could see proper parameters. When i click on TNSNAMES Editor i could see 3 entries . 1. XE 2. EXTPROC\_CONNECTION\_DATA 3.ORACLR\_CONNECTION\_DATA Also i plsql developer if i am able to connect .I am able to connect with out any issues. ---
**Author:** ![anand.coimbatore](https://avatars.discourse-cdn.com/v4/letter/a/e0b2c6/32.png) [@anand.coimbatore](https://forums.toadworld.com/u/anand.coimbatore)\ **Post date:** [June 25, 2013, 11:43am UTC](https://forums.toadworld.com/t/could-not-resolve-the-tns/19291/2 "2013-06-25T11:43:48Z")
ORA-12154: TNS:could not resolve the connect identifier specified Cause: A connection to a database or other service was requested using a connect identifier, and the connect identifier specified could not be resolved into a connect descriptor using one of the naming methods configured. For example, if the type of connect identifier used was a net service name then the net service name could not be found in a naming method repository, or the repository could not be located or reached. Action: - If you are using local naming (TNSNAMES.ORA file): - Make sure that “TNSNAMES” is listed as one of the values of the NAMES.DIRECTORY\_PATH parameter in the Oracle Net profile (SQLNET.ORA) - Verify that a TNSNAMES.ORA file exists and is in the proper directory and is accessible. - Check that the net service name used as the connect identifier exists in the TNSNAMES.ORA file. - Make sure there are no syntax errors anywhere in the TNSNAMES.ORA file. Look for unmatched parentheses or stray characters. Errors in a TNSNAMES.ORA file may make it unusable. - If you are using directory naming: - Verify that “LDAP” is listed as one of the values of the NAMES.DIRETORY\_PATH parameter in the Oracle Net profile (SQLNET.ORA). - Verify that the LDAP directory server is up and that it is accessible. - Verify that the net service name or database name used as the connect identifier is configured in the directory. - Verify that the default context being used is correct by specifying a fully qualified net service name or a full LDAP DN as the connect identifier - If you are using easy connect naming: - Verify that “EZCONNECT” is listed as one of the values of the NAMES.DIRETORY\_PATH parameter in the Oracle Net profile (SQLNET.ORA). - Make sure the host, port and service name specified are correct. - Try enclosing the connect identifier in quote marks. See the Oracle Net Services Administrators Guide or the Oracle operating system specific guide for more information on naming.